The Paton Welding Journal, 2016, №04



2016 №04 (02)

DOI of Article 10.15407/tpwj2016.04.03

2016 №04 (04)

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The Paton Welding Journal, 2016, #4, 32-38 pages
 

Modelling of residual stresses, radiation swelling and stressed state of in-service WWER-1000 reactor baffle

O.V. Makhnenko, I.V. Mirzov and V.B. Porokhonko

E.O. Paton Electric Welding Institute, NASU 11 Kazimir Malevich Str., 03680, Kiev, Ukraine. E-mail: office@paton.kiev.ua
 
 
Abstract
The question of effect of baffle residual welding stresses on radiation swelling value has appeared in course of works on life extension of WWER-1000 reactor internals at the second power generating unit of the South-Ukrainian NPP. The E.O. Paton Electric Welding Institute has developed and realized a mathematical model for determination of residual stress-strain state of WWER-1000 reactor baffle in electroslag welding with further heat treatment as well as a model for calculation of baffle radiation swelling taking into account radiation creep. It can be stated based on the results of mathematical modelling that the baffle stressed state after 60 years of operation, calculated taking into account residual welding stresses, is close to the results received using the model without welding. This work studies relaxation of residual welding stresses in the WWER-1000 baffle under effect of irradiation and works out their in-service value-to-time dependence. 15 Ref., 3 Tables, 11 Figures.
 
Keywords: WWER-1000, baffle, electroslag welding, residual welding stresses, heat treatment, radiation swelling, radiation creep, mathematical modelling
 
 
 
Received: 16.02.2015
Published: 02.06.2016
 
 
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